Kate and Gerry McCann, both 49, have been fighting a lengthy legal battle against Goncarlo Amaral after he wrote a book suggesting they were responsible for the abduction and ‘’death’’ of their daughter in 2007.

The case has been in and out of court in Portugal with Amaral initially being ordered to pay £360,000 damaged in 2015 for the outrageous slurs in ‘The Truth of the Lie’.

But his legal team overturned that order and Kate and Gerry took out their own appeal against him in Portugal’s Supreme Court and earlier this year they were left devastated after judges again ruled in his favour.

In their 76 page ruling judges said Kate and Gerry had not ‘’successfully proved their innocence’’ - which left the couple from Rothley, Leicestershire ‘shattered’, according to a source close to the couple.

Initially they had considered dropping the whole case against Amaral they are more determined than ever that he should not get away with his vile allegations against them.

So far no money has been paid by either party and now they will square up to each other at the European Court of Human Rights in Strasbourg.

The appeal was lodged in July by their Portuguese lawyer Isabel Duarte and they are now waiting for a date to be confirmed.

A source close to the couple said: "They discussed the situation with their legal team and they decided that ultimately it was worth fighting the decision of the Portuguese court.

"They are upset that the court made this ruling but are also desperately upset at Amaral’s claims which are ludicrous and hurtful.’’

Last night the European Court of Human Rights confirmed an appeal had been lodged and officials were investigating its "admissibility’’ before deciding what to do next.

Family spokesman Clarence Mitchell told The Sun: "I can confirm that Kate and Gerry have lodged an appeal application at the European Court of Human Rights and the application is being considered.

"As such they will not be making any comment until a decision has been made. The case is being handled by their legal team in Portugal.

Insiders said it could take almost four years before a decision on whether to proceed in the case is made.

Maddie, three, disappeared in May 2007 from her parents holiday apartment in Praia da Luz on Portugal’s popular

Algarve coast while her younger twin siblings Amelie and Sean, now aged 12, were in the same room.

Earlier this week British detectives investigating her disappearance asked the Home Office for more cash so they could "pursue one final lead’’.